Ping Jim Dowdy, 4E27 questions

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Hey Jim,
so far you're the only one I know of who's played with the 4E27, though I know Douglas had talked about it. I started work on an amp with one, but railroaded myself into an 811a amp, mostly because I didn't have any 4E27 yet. Well what do you know, I scored some.
Mostly I'm concerned about grid current. Most 813 designs use a fairly low value grid resistor because of this. I plan on using direct coupled partial feedback (ala Gary P), and I'm not sure how well the high rp of a pentode driver will work dc coupled to the 4E27. I suspect this may be the cause of some untimely deaths I've experienced with HY69s in a similiar circuit, though that may have just been bad luck. (No I didn't lose bias all you dc coupling nay sayers)
In any case anything useful you learned running these tubes could be helpful. Of course their may also be some differences in running 4E27 versus 4E27a
Thanks

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Parts Connexion

Topic - Ping Jim Dowdy, 4E27 questions - ottoamps 21:26:17 02/05/06 (2)

4E27 - Jim Dowdy 09:42:41 02/06/06 (1)

Hmmmm, Great Minds? - ottoamps 15:35:29 02/06/06 (0)

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